Abstract

There is provided a method of sludge treatment. The method comprises the steps of: - obtaining a sludge, preferably from a wastewater treatment plant; - dewatering the sludge to obtain dewatered sludge and sludge water; - heat-treating the dewatered sludge, optionally after dilution, which heat-treating step comprises separation into a heat-treated slurry and a second fraction, which has lower total suspended solids (TSS) than the heat-treated slurry; - subjecting the second fraction to wet oxidation to obtain a wet-oxidized fraction; - flashing the wet-oxidized fraction in at least one step to obtain at least one steam fraction and a cooled wet-oxidized fraction; - mixing sludge water from the dewatering step with the cooled wet-oxidized fraction to obtain a reject water mixture, wherein the temperature of the reject water mixture is higher than the temperature of the sludge water supplied to said mixing; and - subjecting the reject water mixture to a bacterial nitrogen removal treatment to obtain treated reject water.

IPC Classes  ?

• C02F 11/08 - Wet air oxidation
• C02F 3/30 - Aerobic and anaerobic processes
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning
• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining

Abstract

There is provided a method of sludge treatment, comprising the steps of: - obtaining a sludge, preferably from a wastewater treatment plant; - dewatering the sludge to obtain dewatered sludge and sludge water; - diluting the dewatered sludge to obtain diluted sludge; - heat-treating the diluted sludge to obtain a heat-treated slurry; - separating the heat-treated slurry into a process water fraction and a solids fraction; and - using at least part of the process water fraction in the step of diluting the dewatered sludge.

IPC Classes  ?

• C02F 11/12 - Treatment of sludge; Devices therefor by de-watering, drying or thickening
• C02F 11/08 - Wet air oxidation
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning
• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining

Abstract

There is provided a method of hydrothermal carbonization of a sludge from a wastewater treatment plant, comprising the steps of: preheating the sludge with at least one first steam fraction to obtain a preheated sludge; further heating the preheated sludge with a second steam fraction to obtain a heated sludge; subjecting the heated sludge to hydrothermal carbonization (HTC) in a reactor to obtain a HTC-treated slurry; mixing the HTC-treated slurry with an oxidizing agent, such as oxygen gas, to obtain a wet-oxidized slurry; subjecting the wet-oxidized slurry to flashing to obtain the second steam fraction and a pre-cooled slurry; subjecting the pre-cooled slurry to flashing in at least one step to obtain the at least one first steam fraction and a cooled slurry; separating the cooled slurry into a liquid fraction and a solids fraction; and routing the liquid fraction to the wastewater treatment plant for further treatment, wherein the second steam fraction is used for heating preheated sludge to the temperature of the HTC reaction. A corresponding system is also provided.

IPC Classes  ?

• C02F 9/00 - Multistage treatment of water, waste water or sewage
• C10L 5/48 - Solid fuels essentially based on materials of non-mineral origin on industrial residues or waste materials
• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 1/06 - Flash evaporation
• C02F 11/08 - Wet air oxidation
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning

Abstract

There is provided a method of hydrothermal carbonization of a sludge, comprising the steps of: a) preheating the sludge to obtain a preheated sludge; b) adding an oxidizing agent, such as oxygen gas, to the preheated sludge; and c) subjecting the sludge from step b) to hydrothermal carbonization (HTC) in a reactor to obtain a HTC-treated sludge.

IPC Classes  ?

• C02F 11/08 - Wet air oxidation
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning
• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C10L 5/46 - Solid fuels essentially based on materials of non-mineral origin on sewage, house, or town refuse

Abstract

There is provided amethod of hydrothermal carbonizationof a sludgefrom a wastewater treatment plant, comprising the steps of: preheating the sludge with at leastonefirst steam fraction to obtain a preheated sludge; further heating the preheated sludge with a second steam fraction to obtain a heatedsludge; subjecting the heated sludge to hydrothermal carbonization (HTC) in a reactor to obtain a HTC-treated slurry; mixing the HTC-treated slurrywith an oxidizing agent, such as oxygen gas, to obtain a wet-oxidized slurry; subjecting the wet-oxidized slurryto flashing to obtain the second steam fraction and a pre-cooled slurry; subjecting the pre-cooled slurryto flashing in at least one step to obtain the at least one first steam fraction and a cooled slurry; separating the cooled slurry into a liquid fraction and a solids fraction; and routing the liquid fractionto the wastewater treatment plant for further treatment, wherein the second steam fraction isused for heating preheated sludge to the temperature of the HTC reaction. A corresponding system is also provided.

IPC Classes  ?

• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 11/08 - Wet air oxidation
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning

Abstract

There is provided a method of hydrothermal carbonization of a sludge, comprising the steps of: a) preheating the sludge to obtain a preheated sludge; b) adding an oxidizing agent, such as oxygen gas, to the preheated sludge; and c) subjecting the sludge from step b) to hydrothermal carbonization (HTC) in a reactor to obtain a HTC- treated sludge.

IPC Classes  ?

• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 11/06 - Treatment of sludge; Devices therefor by oxidation
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning

Abstract

There is provided a method of hydrothermal carbonization of a sludge, comprising the steps of: preheating the sludge to obtain a preheated sludge; mixing the preheated sludge with a wet-oxidized fraction to obtain a reaction mixture; subjecting the reaction mixture to hydrothermal carbonization (HTC) in a reactor to obtain a HTC- treated sludge; separating a fraction from the HTC- treated sludge; and mixing the fraction with an oxidizing agent, such as oxygen gas, to obtain the wet-oxidized fraction, wherein the temperature of the fraction before the wet oxidation is at least 15 °C higher than the temperature of the preheated sludge. A corresponding system is also provided.

IPC Classes  ?

• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning

Abstract

There is provided a method of treatment of sludge, such as municipal or industrial sludge from a wastewater treatment plant, comprising the steps of: —preheating an incoming sludge with at least one steam fraction, preferably by direct steam injection, to obtain a preheated sludge; —further heating the preheated sludge with a high-temperature steam fraction, preferably by direct steam injection, to obtain a heated sludge; —hydrothermal carbonization (HTC) of the heated sludge to obtain a HTC-treated sludge; —separating a particle-lean fraction from the HTC-treated sludge; —wet oxidation of the particle-lean fraction to obtain a heated particle-lean fraction; —subjecting the heated particle-lean fraction to a first flashing to obtain the high-temperature steam fraction used in the further heating step; —separating a particle-rich fraction from the HTC-treated sludge; —subjecting the particle-rich fraction to flashing to obtain at least one steam fraction that is used in the preheating step and a cooled particle-rich fraction.

IPC Classes  ?

• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C10L 5/46 - Solid fuels essentially based on materials of non-mineral origin on sewage, house, or town refuse
• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 11/08 - Wet air oxidation
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning
• C02F 103/34 - Nature of the water, waste water, sewage or sludge to be treated from the chemical industry not provided for in groups

Abstract

A method and system for the treatment of sludge in a chemical pulp mill including a step of hydrothermal carbonization (HTC) of a sludge stream, wherein said sludge stream is fed into a HTC arrangement and subjected to elevated temperature and pressure, producing at least one solids fraction, at least one liquid fraction, and at least one gaseous fraction; wherein said solids fraction is fed to a power boiler of said pulp mill and burned to generate steam; said liquid fraction is combined with weak black liquor from the pulp mill and fed to a black liquor evaporator of said pulp mill, and the resulting concentrated black liquor is burned in a recovery boiler of said pulp mill.

IPC Classes  ?

• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning
• D21C 11/00 - Regeneration of pulp liquors

Abstract

There is provided a method of treatment of sludge, such as municipal or industrial sludge from a wastewater treatment plant, comprising the steps of: -preheating an incoming sludge with at least one steam fraction, preferably by direct steam injection, to obtain a preheated sludge; -further heating the preheated sludge with a high-temperature steam fraction, preferably by direct steam injection, to obtain a heated sludge; -hydrothermal carbonization (HTC) of the heated sludge to obtain a HTC-treated sludge; -separating a particle-lean fraction from the HTC-treated sludge; -wet oxidation of the particle-lean fraction to obtain a heated particle-lean fraction; -subjecting the heated particle-lean fraction to a first flashing to obtain the high-temperature steam fraction used in the further heating step; -separating a particle-rich fraction from the HTC-treated sludge; -subjecting the particle-rich fraction to flashing to obtain at least one steam fraction that is used in the preheating step and a cooled particle-rich fraction.

IPC Classes  ?

• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining
• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning

Abstract

There is provided a container adapted to be transported by a truck, in which container a system for sludge treatment is arranged, said system comprising: a reactor (104) for heat treatment of a sludge; a cooling arrangement (107, 114) for cooling sludge treated in the reactor (104) and preheating sludge transported from a sludge inlet (102) to the reactor (104); and a separation arrangement (118, 126) for separating cooled sludge from the cooling arrangement into a first fraction (129) and a second fraction (124), wherein the suspended solids content is higher in the first fraction (129) than in the second fraction (124), wherein the container comprises a lower floor and an upper floor provided above the lower floor to support at least part of the system and form an interspace between the lower floor and the upper floor and wherein the interspace is in fluid communication with a space above the upper floor such that sludge leaked from a position above the upper floor is collected in the interspace.

IPC Classes  ?

• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C10L 9/08 - Treating solid fuels to improve their combustion by heat treatment, e.g. calcining

Abstract

There is provided a system for sludge treatment, which system is arranged in a container adapted to be transported by a truck and comprises: a sludge inlet for receiving a sludge; a reactor comprising an electrical heating arrangement for heat treatment of the sludge, which reactor is arranged downstream the sludge inlet; a flashing arrangement for cooling sludge treated in the reactor and providing at least one steam fraction, which flashing arrangement is arranged downstream the reactor; a steam routing arrangement capable of routing the at least one steam fraction from the flashing arrangement to preheat sludge transported from the sludge inlet to the reactor; and a separation arrangement for separating the cooled sludge from the flashing arrangement into a first fraction and a second fraction, wherein the suspended solids content is higher in the first fraction than in the second fraction. A corresponding method is also provided.

IPC Classes  ?

• C02F 11/10 - Treatment of sludge; Devices therefor by pyrolysis
• C02F 11/18 - Treatment of sludge; Devices therefor by thermal conditioning